In triangle ABC, the size of angle B is 5 times the size of angle A, and the size of angle C is 18° less than 4 times the size of angle A?

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Answer 1 · 2018-01-14T02:29:36

#/_A=19.8^@#, #/_B=99^@#, and #/_C=61.2^@#

Recall that the total sum of inner angles of a triangle is #180^@#.

Since #/_B=5/_A# and #C=4/_A-18^@#

Then we can say

#180^@=/_A+5/_A+4/_A-18^@#

Then we can simplify and get

#198^@=10/_A#

Then

#/_A=19.8^@#

Then we plug in to get

#/_B=99^@#

and

#/_C=61.2^@#

In triangle​ ABC, the size of angle B is 5 times the size of angle​ A, and the size of angle C is 18° less than 4 times the size of angle A?